
Essentially, PGI moved anywhere between 200K to 900K units of MW5 prior to the relaunch, with that factored in we're looking at 360K - 1.1M. Sales on non-Steam platforms (ie Xbox and GOG, probably also including post-exclusivity sales on Epic) amount to 30.5K total units.
Now, keep in mind that they include DLC in these sales (not clear if buying the Dropship Edition counts as one or two copies) and that's kind of underwhelming by modern standards.